1. Field of the Invention
The present invention relates to a work arrangement apparatus. More particularly, the present invention relates to a work arrangement apparatus for arranging pieces of plate-shaped work, such as lead frames or printed boards, in such a manner that the pieces of plate-shaped work are piled up while being interposed between sheets of interlayer paper.
2. Description of the Related Art
Lead frames, which are formed into slender rectangles, or printed boards, which are formed into individual pieces, are accommodated in accommodation cases being piled up so that they can be conveyed between factories after the completion of a predetermined inspection. When the lead frames or printed boards are piled up and accommodated in the accommodation cases, in order to prevent them from being damaged or deformed, sheets of interlayer paper are interposed, between the lead frames or printed boards, one by one.
The sheets of interlayer paper are formed into the same external shape as that of the lead frames and others. For example, in the case of piling up lead frames, the shapes of which are formed into slender rectangles, sheets of interlayer paper, the shapes of which are formed into the same slender rectangles, are used.
The lead frames or printed boards are piled up by an automated apparatus while the sheets of interlayer paper are interposed between them. Concerning the automated apparatus for piling up the lead frames or printed boards, for example, there is provided an apparatus in which, while lead frames, the shapes of which are formed into slender rectangles, are being sent into an accommodation tray one by one, each time the lead frame is supplied to the accommodation tray, a sheet of interlayer paper is put on the lead frame, so that the lead frames and the sheets of interlayer paper can be alternately piled up. This technique is disclosed, for example, in JP-A-2-86519.
As a method of piling up pieces of work such as lead frames, the shapes of which are formed into slender rectangles, or printed boards, which are formed into individual pieces, while sheets of interlayer paper are being interposed between them, it is common to use the above method in which the sheets of interlayer paper are supplied to a position at which the pieces of work are piled up, and the pieces of work and the sheets of interlayer paper are alternately piled up.
However, the above method in which the pieces of work and the sheets of interlayer paper are respectively sent to the same position and alternately piled up has the following disadvantages. The piling time for one time includes the time necessary for feeding a piece of work and the time necessary for supplying a sheet of interlayer paper. Therefore, even when feeding operation is conducted at high speed, it is technically difficult to conduct piling operation of one time in a short period of time of not more than 1 second.
Further, the following problems may be encountered. In the case of the conventional work arrangement apparatus, in the case where products to be arranged are changed, it is necessary to adjust the apparatus according to the work width. Further, in the case where each piece of work is positioned when it collides with a stopper, the work is damaged.